Serena Williams said emotions got the best of her when things got hostile between her and a chair umpire at the U.S. Open this weekend.

The tennis star earned herself plenty of scorn during her match with Australian Sam Stosur, which the American eventually lost. After allowing the heat to swirl for a few days, Williams took to Twitter to air a mea culpa.

"My emotions did get the best of me this past weekend when I disagreed with the umpire," Willams tweeted. "It has been a long road to get back to the US Open this year, and I am thankful to have had such a great two weeks in New York."